The PenPal - a portable communications device for children aged four to six -
was designed and prototyped at Stanford University in the context of the
1994 Apple Interface Design Competition. The PenPal enables children
to learn by creating images and sending them across the Internet to a real
audience of friends, classmates, and teachers. A built-in camera and microphone
allow children to take pictures and add sounds or voice annotations. The
pictures can be modified by plugging in different tools and sent through the
Internet using the PenPal Dock.

The limited symbolic reasoning and planning
abilities, short attention span, and pre-literacy of children in this age range
were taken into account in the PenPal design. The central design philosophy and
main contribution of the project was to create a single interface based on
continuity of action between hardware and software elements. The physical
interface flows smoothly into the software interface, with a fuzzy boundary
between the two.

The PenPal project received awards for "Best
Hardware/Software Integration and User Involvement" and "Best
Presentation" as well as a distinction in the ID Magazine annual
competition (student category.)

Presentations and Publications

One of the first class assignments was to understand the target user group
(in this case children aged four to six) and how the product could be used.
Various
scenarios were generated
showing different tasks that could be performed with the PenPal device.

This final presentation summarizes the design
steps the team went through during this project: (1) understanding the users,
(2) developing usage scenarios, (3) prototyping key interaction elements and
(4) conducting usability tests.
It got the team selected to go present its work at Apple Computer.

After the competition was over the PenPal project was
presented at the Conference on Computer Human
Interaction '95 in Denver (the corresponding conference paper is available below.)

In order to understand the issues in merging physical and screen interfaces, a
software prototype
was developed and tested.
To model the physical interactions, a touch-screen was taped onto a computer monitor and a large-scale
cardboard mock-up of the PenPal was taped on top of the touch-screen. The cardboard mock-up included
the main hardware features of the PenPal: two tool slots, and a coaching button at the top of the screen.
The software was controlled through a combination of behind-the-scenes manipulation by a project member
and of direct user interaction with the touch-screen.